bugfix: treating a unique index conflict during rollback as a dirty write

changes/en-us/2.x.md

@@ -17,6 +17,7 @@ Add changes here for all PR submitted to the 2.x branch.
 - [[#7112](https://github.com/apache/incubator-seata/pull/7112)] bugfix: remove the condition that IPv6 must start with fe80
 - [[#7107](https://github.com/apache/incubator-seata/pull/7107)] fix the issue of failing to parse annotations in TCC mode when the business object is a proxy object.
 - [[#7124](https://github.com/apache/incubator-seata/pull/7124)] bugfix: GlobalTransactionScanner.afterPropertiesSet need do scanner check
+- [[#7135](https://github.com/apache/incubator-seata/pull/7135)] treating a unique index conflict during rollback as a dirty write
 
 
 ### optimize:
@@ -59,5 +60,6 @@ Thanks to these contributors for their code commits. Please report an unintended
 - [xiaoxiangyeyu0](https://github.com/xiaoxiangyeyu0)
 - [wxrqforever](https://github.com/wxrqforever)
 - [xingfudeshi](https://github.com/xingfudeshi)
+- [YongGoose](https://github.com/YongGoose)
 
 Also, we receive many valuable issues, questions and advices from our community. Thanks for you all.

changes/zh-cn/2.x.md

@@ -17,6 +17,7 @@
 - [[#7112](https://github.com/apache/incubator-seata/pull/7112)] 校验是否IPv6网络ip取消必须以fe80开始的条件
 - [[#7107](https://github.com/apache/incubator-seata/pull/7107)] 修复tcc模式下，当业务对象为代理对象时，解析注解失败问题。
 - [[#7124](https://github.com/apache/incubator-seata/pull/7124)] GlobalTransactionScanner.afterPropertiesSet方法需要做扫描检查
+- [[#7135](https://github.com/apache/incubator-seata/pull/7135)] 回滚时遇到唯一索引冲突视为脏写
 
 ### optimize:
 
@@ -58,5 +59,6 @@
 - [xiaoxiangyeyu0](https://github.com/xiaoxiangyeyu0)
 - [wxrqforever](https://github.com/wxrqforever)
 - [xingfudeshi](https://github.com/xingfudeshi)
-- 
+- [YongGoose](https://github.com/YongGoose)
+
 同时，我们收到了社区反馈的很多有价值的issue和建议，非常感谢大家。

rm-datasource/src/main/java/org/apache/seata/rm/datasource/undo/AbstractUndoLogManager.java

@@ -298,6 +298,7 @@ public void flushUndoLogs(ConnectionProxy cp) throws SQLException {
      * @param xid             the xid
      * @param branchId        the branch id
      * @throws TransactionException the transaction exception
+     * @throws BranchTransactionException the branch transaction exception
      */
     @Override
     public void undo(DataSourceProxy dataSourceProxy, String xid, long branchId) throws TransactionException {
@@ -363,6 +364,9 @@ public void undo(DataSourceProxy dataSourceProxy, String xid, long branchId) thr
                                     dataSourceProxy.getDbType(), sqlUndoLog);
                             undoExecutor.executeOn(connectionProxy);
                         }
+                    } catch (SQLIntegrityConstraintViolationException ex) {
+                        throw new BranchTransactionException(BranchRollbackFailed_Unretriable,
+                                String.format("Branch session rollback failed. xid = %s branchId = %s", xid, branchId), ex);
                     } finally {
                         // remove serializer name
                         removeCurrentSerializer();